The basis of error detection and error correction of data stored in storage devices relies in the incorporation of redundant information to the data. The redundant information (also known as parity or redundancy symbols) is used by special hardware and/or software to detect and correct errors in order to recover missing or corrupt data within a media of the storage device. The data residing in a storage device, such as a magnetic disk drive, is encoded using two types of codes: an error correction code (ECC) and an error detection code (EDC). ECCs are used to correct errors while EDCs are used to detect errors in data as it is read from the storage device. Unfortunately, in many instances, such ECCs and EDCs utilize algorithms, implemented either in hardware or firmware, that are incapable of recovering the data in the storage device.
When employing ECC and EDC to data stored in a magnetic disk drive, the number of errors (e.g., symbols errors) capable of being corrected in a sector of data is limited to a specific maximum number. Unfortunately, when the number of such errors exceeds this maximum number, the data associated with this sector may not be readable. As a consequence, critical data may never be recovered from the magnetic disk drive.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.